foo.cc: In function 'long long int solve(long long int)':
foo.cc:6:5: error: 'reruen' was not declared in this scope
     reruen 1;
     ^~~~~~
foo.cc:6:5: note: suggested alternative: 'freopen'
     reruen 1;
     ^~~~~~
     freopen
foo.cc:8:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^

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